Coating for metal molds



Patented Nov. '10, 1925.

uuirsos'rarss PATENT OFFICE.

DANIEL H. HELOOHE, OF DETROIT, MICHIGAN, ASSIGNOR '10 EARL HOLLEY, OF

- 'DIE'.'I.B-O]Z'.I., MICHIGAN. I

coa'rme son METAL norms.

no Drawin'g. Application filed January 10, 1925. Serial No. 1,581.

issued August 26,1924, so as to build up a To all whom it may concern coatmg of a substantial thickness (.02 to Be it known that I, DANIEL Hpumioorrn,

a citizen of the United States, residing at .04"). I I p 2490 Hazelwood Ava, Detroit, in the county Any high grade fire clay may be used, or 5 of VVa-yne and State of Michigan, have in-- for that matter any high grade refractoryin' vented certain new and useful Improvelhe powdered form. However, the fire clay ments in Coatings for Metal Molds, of" which I use has a composition as follows I which the followiug is a specification.v Per cent This invention relates to an improved g jw iti (H O) 12 8 coating for the protection of the surface oi a I 50 metal molds exposed to "the molteu metal. 6 "I" 9 This invention relates specifically to the pro- F 25 tection of cast iron molds'when used for the 5 n 45 V production of iron castings in which a re- 5 i 15 fractory coating is used next to the metal of K 6 7 the molds and in which a superimposed coat- 6 '7' jug of lampblack is also used. ,;";66 'd };i""T"7 Thisapplication is an improvement on the i invention disclosed in my Patent #1,453,593, \Vhat I. claim is 1. A wash for giving a protective coating filed August 11, 1 922,]issued May 1, 1923. I have discovered that among the various grades of sodiumsilicate that are availableas a binder there is one, known commercially as grade C,.which has superior binding to metal molds, comprisingwater contain-- mg a small quant1ty of C, grade sodium silicate m solution and a relatlvely large 05 qualities which enables the refractory coating to withstand the action of the molten iron for a larger number of castings than do the other grades.

Grade G contains 16.88%, by weight, of

sodium oxide, 35.80% of silica, and 46.88% of water, and can therefore be represented by the formula (Na O);-,(SiO,) (H O) iis grade is relatively heavy, 10 'flul ounces weighing approximaely one pound.

-This sodium silicate is used as follows Five parts by weight are dissolved in seventy parts by weight of. waterfand into this dilute solution twenty-five parts by wei ht of powdered fire clay are stirred. A t in wash is thus formed which is applied in thin layers onto a heated mold, as described in my Patent #1,506,130, filed lllarch 14;, 1923,

to metal mold seventy parts of water by In testimony quantity of a refractory powder in suspension. v

2. A wash for giving a protective coating 3. A wash for giving a protective coating 76 to metal molds, comprising substantially weight in which is dissolved five parts b C sodium silicate, an pended twenty-five parts powdered fire cl in which is sus- Damnn H. MELO'CHE.

s, comprising substantially seventy parts of waterby weight in which weight of grade by weight of 0 a Y t 7 hereof I'aflix my signature. 

